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CASE STUDY

ENGINEERING

SERVICES

GROUP

www.qualcomm.com/esg

Delivering technical evaluations and services to network

operators worldwide

The following case documents how

Qualcomm ESG used its proprietary QUEST

network simulation tool and novel parameter

optimization techniques at special event venues

(sports arenas, convention centers, concert

amphitheatres) to maximize network capacity

and maintain a high quality user experience.

AT ISSUE

Maintaining a consistent, high quality user experience at special events

The performance of 3G wireless networks during special events poses a unique

problem. The large concentration of smartphones with a usage profile of frequent,

short data connections reduces network efficiency and lowers downlink and uplink

capacity. This causes low call completion rates, frequent dropped calls, suboptimal

response times, and low throughputs. The degraded user experience can lead to

subscriber churn and often visible, public backlash.

THE CHALLENGE

Effectively dimensioning & maximizing UMTS network capacity during

special eventsOperators need a solution to accurately dimension their network resources and to

maximize network capacity for the unique RF conditions of special events.

Accurately estimating voice and data traffic demand during a special event, and

properly modeling the estimation to predict user experience with the deployed

capacity is quite complex. This is compounded by the capacity lost due to large

amounts of Radio Resource Control (RRC) signaling generated by the always

connected smartphone devices, a factor which traditional network dimensioning

techniques often overlook. Figure 1 illustrates the impact of excessive signaling at an

under-dimensioned venue: very low voice and R99 data traffic with very high

non-HS power consumption due to signaling that impacts connection accessibility

and retainability.

With inputs such as accurate data usage, device mix, traffic patterns andapplication type, the network resources can be adequately dimensioned and then

optimized for an improved user experience during special events.

SITUATION

u Large concentrations of subscribers

simultaneously access the 3G network

during special events.

u The typical smartphone usage patternof frequent, short data connections

increases network load, causing a

degraded user experience.

u Estimating user experience, particularly

for data traffic, during special events

is very challenging with the currently

available commercial tools.

SOLUTION

u Used QUEST simulation tool to

estimate data traffic demand and

validate user experience based on the

deployed capacity.

u Recommended specific networkparameter optimization settings to

reduce RRC connections.

RESULTS FROM SELECTED VENUES

u 90% reduction in inter-RAT related

RRC connections.

u 30% reduction in number of PS

connections.

u 50% reduction in number of FACH-to-

HS transitions.

u Optimized data throughput and

capacity management.

UMTS NETWORK OPTIMIZATION AT SPECIAL EVENT VENUES

Optimizing major stadiums for the

2010 FIFA World Cup with MTN

South Africa

The growth of 3G-capable smart phone

is allowing more people to enjoy wireless

data services while attending sporting

events, says Sameer Dave, chief technol

gy officer of MTN South Africa. This tren

brings unique network demands in

supporting large groups of subscribers i

a relatively small geographic area.Qualcomms engineering support was in

strumental in helping us ensure that spe

tators received the reliable, high-speed

voice and data services they have come

expect from MTN South Africa.

- Aug 17, 2010 www.qualcomm.com/pres

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ENGINEERING

SERVICES

GROUP

www.qualcomm.com/esg

Cell0

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kbps

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THE SOLUTION

Partnering with Qualcomm to achieve maximum

network capacity

Qualcomm ESG optimized special event venues for several

tier-one operators to improve connection performance and

maximize system capacity using its QUEST simulation tool

and implementing novel parameter optimization techniques.

The goal was to estimate the capacity demand, accurately

dimension the network resources, develop the best possible

network design, and optimize the system parameters to maximize the capacity.

Qualcomm ESG employed QUEST to estimate the user experience for the forecasted

traffic and the deployed capacity at the special event venues. This validated the

deployed distributed antennae systems (DAS) design for the venues. QUEST used real-world network data for a given mix of inputs such as morphology, device mix, traffic

patterns, and application type. With this, QUEST accurately simulated the smartphone

traffic typically seen during special events and predicted the resulting traffic signaling.

Qualcomm ESG also analyzed the performance counters from prior special events at

each of the venues. The analysis revealed ping-pongs between WCDMA and underlying

GSM networks, inefficient usage of RRC states in data calls, and a significant number

of registrations. The excessive traffic generated due to registrations was minimized by

streamlining the periodic registration timers and inter-RAT cell reselection parameters

(both WCDMA to GSM and GSM to WCDMA). The PS connections were reduced, thereby

maximizing system capacity, by optimizing the (Forward Access Channel) FACH-Idle

inactivity timer, FACH buffer thresholds, and HSDPA cell change timer parameters.

RESULTSIncreasing capacity, providing uniform coverage and improving user

experience

Qualcomm ESG delivered comprehensive reports to the operators detailing the issues,

root causes and specific recommendations. Recommendations were tested at various

special event venues to achieve the below results.

u Actual user throughput estimated within 10% accuracy by using QUEST simulation

tool. See Figure 2.

u 90% reduction in registration and inter-RAT related RRC connections by increasing

the periodic registration timer from 1 hour to 3 hours and aggressively setting inter-

RAT cell reselections.

u 10% reduction in number of PS connections by increasing FACH-Idle inactivity

timer from 10 to 30 seconds.

u >30% reduction in number of PS connections by increasing FACH-Idle inactivity

timer from 10 to 300 seconds.

u Approximately 50% reduction in number of FACH-to-HS transitions by increasing

FACH to DCH/HS up-switch thresholds.

UMTS NETWORK OPTIMIZATION AT SPECIAL EVENT VENUES | CASE STUDY

2011.01 .V0

FIGURE 1: DL Power Utilization vs. Traffic

FIGURE 2: QUEST estimates actual user

throughput within 10% accuracy

FIGURE 3: Results from selected venues

About Qualcomm ESG

Qualcomm Engineering Services Group(ESG) provides technical consultation and

educational services for mobile technologi

from launching a mobile technology to

optimizing and troubleshooting mature

technologies.

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